Circuit connection material, circuit member connecting structure and method of connecting circuit member

Abstract

The circuit-connecting material for connection between circuit members each having a board and a circuit electrode formed on the primary surface of the board, comprising an adhesive composition that cures in response to light or heat and an organic compound containing a urethane group and an ester group.

The invention claimed is: 
     
       1. A circuit-connecting material for connection between circuit members, wherein each circuit member has a board and a circuit electrode formed on a primary surface of said board, the material comprising:
 (a) an adhesive composition that cures in response to light or heat; and 
 (b) an organic compound comprising a urethane group and an ester group, wherein the organic compound has a weight-average molecular weight of 5,000 to 100,000. 
 
     
     
       2. A circuit-connecting material according to  claim 1 , wherein said adhesive composition includes a radical polymerizing compound and a radical initiator that generates radicals in response to heat or light. 
     
     
       3. A circuit-connecting material according to  claim 2 , wherein said radical polymerizing compound comprises a phosphoric acid ester compound with an acrylate group or methacrylate group. 
     
     
       4. A circuit-connecting material according to  claim 1 ,
 wherein the glass transition temperature of said organic compound is 50° C. or higher. 
 
     
     
       5. A circuit-connecting material according to  claim 1 , wherein said organic compound includes either or both of an aromatic group and a cyclic aliphatic group. 
     
     
       6. A circuit-connecting material according to  claim 1 ,
 wherein the weight-average molecular weight of said organic compound is 5,000 to 60,000. 
 
     
     
       7. A circuit-connecting material according to  claim 1 ,
 which further comprises conductive particles. 
 
     
     
       8. A circuit-connecting material according to  claim 1 , wherein the weight-average molecular weight of said organic compound is 27,000 to 60,000. 
     
     
       9. A cured product of a circuit-connecting material according to  claim 1 , wherein the cured product of the circuit-connecting material electrically connects a first circuit member and a second circuit member, wherein the first circuit member has a first board and a first circuit electrode formed on a primary surface of the first board, and the second circuit member has a second board and a second circuit electrode formed on a primary surface of the second board. 
     
     
       10. A circuit member connection method comprising the steps of:
 providing a first circuit member provided with a first board and a first circuit electrode formed on a primary surface of the first board, a first layer made of a circuit-connecting material according to  claim 1 , and a second circuit member provided with a second board and a second circuit electrode formed on a primary surface of the second board; and 
 heating and pressing the first circuit member, the first layer and the second circuit member as a laminate prepared by laminating the first circuit member, the first layer and the second circuit member in that order with the first circuit electrode and the second circuit electrode opposing each other in order to connect the first circuit member and the second circuit member so that the first circuit electrode and the second circuit electrode are electrically connected. 
 
     
     
       11. A circuit member connection method according to  claim 10 , wherein a surface of at least one of said first circuit electrode and said second circuit electrode comprises a material including at least one substance selected from the group consisting of gold, silver, tin, platinum-group metals and indium tin oxide. 
     
     
       12. A circuit member connection method according to  claim 10 , wherein at least one of said first board and said second board is a board formed of a material comprising one or more substances selected from the group consisting of polyethylene terephthalate, polyethersulfone, epoxy resins, acrylic resins, polyimide resins and glass. 
     
     
       13. A circuit member connection method according to  claim 10 , wherein a second layer comprising one or more resins selected from the group consisting of silicone resins, acrylic resins and polyimide resins is formed between at least one of said first circuit member and said second circuit member and the first layer made of said circuit-connecting material. 
     
     
       14. A circuit member connection structure comprising:
 (a) a first circuit member comprising a first board and a first circuit electrode formed on a primary surface of the first board; and 
 (b) a second circuit member comprising a second board and a second circuit electrode formed on a primary surface of the second board, wherein the first circuit member and the second circuit member are connected by a circuit-connecting member made of a cured product of a circuit-connecting material formed between the first circuit member and the second circuit member so that the first circuit electrode and the second circuit electrode are opposing each other and are electrically connected, wherein the circuit-connecting material comprises
 i. an adhesive composition that cures in response to light or heat; and 
 ii. an organic compound comprising a urethane group and an ester group, 
 
 wherein the organic compound has a weight-average molecular weight of 5,000 to 100,000. 
 
     
     
       15. A circuit member connection structure according to  claim 14 , wherein a surface of at least one of the first circuit electrode and the second circuit electrode comprises a second material containing at least one substance selected from the group consisting of gold, silver, tin, platinum-group metals and indium tin oxide. 
     
     
       16. A circuit member connection structure according to  claim 14 , wherein at least one of the first board and the second board is a board made of a second material comprising one or more components selected from the group consisting of polyethylene terephthalate, polyethersulfone, epoxy resins, acrylic resins, polyimide resins and glass. 
     
     
       17. A circuit member connection structure according to  claim 14 , wherein a layer comprising one or more resins selected from the group consisting of silicone resins, acrylic resins and polyimide resins is formed between at least one of said first circuit member and said second circuit member and said circuit-connecting member.